My company produces electronic devices in EU and sell them all over the world. We have a disposal center in UK to comply with the WEEE regulation (Waste Electrical and Electronic Equipment) for disposal. But what can we do for the units sold outside EU? It does not make sense to ship them back to UK to be scrapped. Can they be dispose outside EU?

However, other similar legislations may apply in the importing country.
If the company that is importing the goods is an affiliate of your company then you may have responsibilities under their local legislation. For example, if you were importing goods into EU then you would be responsible to ensure the implementation of the WEEE.